Hydrogen sulfide (H2S) and organic sulfides are found within geological formations associated with oil and gas reserves. Due to their toxicity and corrosive nature, they are generally reduced or removed from hydrocarbon streams during production in a process called “sweetening.” A common approach is to use an H2S scavenger, particularly triazine, which is produced by an aldehyde and an amine reaction. The H2S scavenger subsequently reacts with the hydrogen sulfide converting it to a more non-volatile product, which can be more easily removed from the hydrocarbon stream. Typical formulations use a low molecular weight aldehyde such as formaldehyde, but ketones can also be used. The amines can be alkylamines as disclosed in U.S. Pat. No. 5,674,377 (filed Jun. 19, 1995), alkanolamines as disclosed in U.S. Pat. No. 4,978,512 (filed Dec. 18, 1989), or even a combination of amines as disclosed in U.S. Pat. No. 6,267,938 B1 (filed Nov. 4, 1996), U.S. Pat. No. 5,347,004 (filed Oct. 9, 1992), and U.S. Pat. No. 5,554,349 (filed Sep. 8, 1994).
While amine-based H2S scavengers are effective at removing hydrogen sulfide from hydrocarbon streams, they are also known to form an unwanted dithiazine byproduct. This so-called amorphous dithiazine is exceptionally insoluble, and substantial quantities can deposit throughout the gas processing system. Dithiazine deposits are a significant problem to the gas processing industry. They can form blockages in gas processing equipment, storage tanks, truck tanks, and water disposal wells. Cleanup procedures are time consuming and difficult. Often, the equipment has to be taken off-line so the deposits can be manually chipped away. The industry places much effort and incurs great cost in the treatment of amorphous dithiazine buildup.